Display device and method of manufacturing the same

ABSTRACT

A display device may include a substrate, pixels, and a crack mitigation structure. The substrate may include a main region, a sub-region, and a bending region. The bending region may be connected between the main region and the sub-region and may include a curved outline section. The pixels may be disposed on the main region. The crack mitigation structure may be disposed on the bending region. A section of the crack mitigation structure may be substantially parallel to the curved outline section.

This application claims priority to Korean Patent Application No.10-2019-0031673 filed on Mar. 20, 2019 in the Korean IntellectualProperty Office; the disclosure of the Korean Patent Application isincorporated herein by reference in its entirety.

BACKGROUND 1. Field

The technical field relates to a display device and a method formanufacturing the display device.

2. Description of the Related Art

Modern display devices include liquid crystal display devices andorganic light-emitting diode display devices. A display device mayinclude a display region and a bent region. The display region mayinclude pixels for displaying images. The bent region may be implementedfor minimizing the overall size of the display device. Because ofcontinuous stress, a crack may occur in the bent region. The crack maypropagate toward the display region and may adversely affect theperformance and/or durability of the display device.

SUMMARY

Embodiments may minimize propagation of a crack in a bending region of adisplay device.

An embodiment of a display device includes a substrate, which includes amain region including a display region, a sub-region including pads, anda bending region disposed between the main region and the sub-region andincluding two outlines of which at least one outline includes a curvedportion, wherein the bending region includes a structure disposed to besubstantially parallel to the curved portion.

An embodiment of a method of manufacturing a display device, the methodincludes: forming at least one barrier layer on a substrate on which amain region and a bending region are defined, wherein the main regionincludes a display region and the bending region extends from one sideof the main region and has two outlines of which at least one outlineincludes a curved portion; forming at least one inorganic layer on thebarrier layer; etching the at least one barrier layer and the at leastone inorganic layer in the bending region to form crack prevention damsincluding at least one barrier layer and at least one inorganic layer;and cutting a boundary between the crack prevention dams on thesubstrate using a laser.

An embodiment may be related to a display device. The display device mayinclude a substrate, pixels, and a structure. The substrate may includea main region, a sub-region, and a bending region. The bending regionmay be connected between the main region and the sub-region and mayinclude a curved outline section. The pixels may be disposed on the mainregion. The structure may be disposed on the bending region. A sectionof the structure may be substantially parallel to the curved outlinesection.

A first end of the structure may be positioned closer to the main regionand farther from a center of the bending region than a second end of thestructure.

The structure may include dams. The dams may be spaced from each otherand may include a dam. A section of the dam may be substantiallyparallel to the curved outline section of the bending region.

The dam may include an inorganic layer.

The inorganic layer may include at least one of a first insulatinglayer, a second insulating layer, and a third insulating layer.

The display device may include a first organic layer overlapping thebending region. The display device may include a signal line provided onthe first organic layer.

The display device may include a driving chip. The driving chip may bedisposed on the sub-region and may be electrically connected through thesignal line to at least one of the pixels.

The display device may include a second organic layer disposed on thefirst organic layer and covering the signal line.

The dam may include at least one of a first organic part and a secondorganic part. A material of the first organic part may be identical to amaterial of the first organic layer. A material of the second organicpart may be identical to a material of the second organic layer.

The dam may include an inorganic part. The inorganic part may bepositioned between the bending region and the first organic part and/orthe second organic part.

The first organic layer may be spaced from the dams.

The bending region may be partially exposed between the dam and thefirst organic layer.

The bending region may be partially exposed between the dams.

The dam may extend continuously from an edge of the main region to anedge of the sub-region.

The dams may be spaced from each other in a first direction and may bespaced from one another in a second direction different from the firstdirection.

The dam may have a trapezoidal shape in a plan view of the bendingregion and may be a first dam. The dams may include a second dam and athird dam. No intervening dam may be positioned between the first damthe second dam. No intervening dam may be positioned between the seconddam and the third dam. The first dam, the second dam, and the third dammay not be all aligned.

An embodiment may be related to a method for manufacturing a displaydevice. The method may include forming a barrier layer on a substrate.The substrate may include a main region and a neighboring region. Theneighboring region may be directly connected to the main region. Thebarrier layer may include a first barrier section and a second barriersection. The first barrier section may overlap the main region. Thesecond barrier section may overlap the neighboring region. The methodmay include forming transistors that overlap the first barrier section.The method may include forming an inorganic layer on the barrier layer.The inorganic layer may include a first inorganic section and a secondinorganic section. The first inorganic section may overlap the firstbarrier section. The second inorganic section may overlap the secondbarrier section. The method may include etching at least the secondbarrier section and the second inorganic section to form dams. Each ofthe dams may include a remaining portion of the second barrier sectionand a remaining portion of the second inorganic section. The method mayinclude cutting the neighboring region at a location between two of thedams using a laser to form a bending region. The bending region mayinclude a curved outline section.

The method may include the following steps: forming an insulating filmon remaining portions of the second inorganic section; and etching theinsulating film at locations between the remaining portions of thesecond inorganic section.

The method may include the following steps: forming a pixel definitionlayer on remaining portions of the insulating film; and etching thepixel definition layer at locations between the remaining portions ofthe insulating film.

The bending region may be partially exposed between remaining dams ofthe dams.

An embodiment may be related to a method for manufacturing a displaydevice. The method may include the following steps: forming aninsulating layer on a substrate, wherein the substrate may include amain region and a neighboring region, wherein the neighboring region maybe directly connected to the main region, wherein the insulating layermay include a first insulating section and a second insulating section,wherein the first insulating section may overlap the main region, andwherein the second insulating section may overlap the neighboringregion; forming transistors that overlap the first insulating section;etching at least the second insulating section to form dams, whereineach of the dams may include a remaining portion of the secondinsulating section; and cutting the neighboring region at a locationbetween two of the dams using a laser to form a bending region, whereinthe bending region may include a curved outline section.

The method may include the following steps: forming an insulating filmon remaining portions of the second insulating section; and etching theinsulating film at locations between the remaining portions of thesecond insulating section.

The method may include the following steps: forming a pixel definitionlayer on remaining portions of the insulating film; and etching thepixel definition layer at locations between the remaining portions ofthe insulating film.

The bending region may be partially exposed between remaining dams ofthe dams.

Embodiments may minimize propagation of a crack in a display device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan/layout view illustrating a display device according toan embodiment.

FIG. 2 is a schematic partial cross-sectional view illustrating thedisplay device according to an embodiment.

FIG. 3 is a plan/layout view illustrating signal lines in a bendingregion of a panel according to an embodiment.

FIG. 4 is a plan/layout view illustrating signal lines in a displaypanel according to an embodiment.

FIG. 5 is an equivalent circuit diagram illustrating a pixel accordingto an embodiment.

FIG. 6 is a partial cross-sectional view illustrating a display moduleaccording to an embodiment.

FIG. 7 is a partial cross-sectional view illustrating a display moduleaccording to an embodiment.

FIG. 8 is a cross-sectional view taken along a line I-I′ shown in FIG. 3according to an embodiment.

FIG. 9 is an enlarged plan view illustrating a region A shown in FIG. 4according to an embodiment.

FIG. 10 is an enlarged plan view illustrating the region A shown in FIG.4 according to an embodiment.

FIG. 11 is an enlarged plan view illustrating the region A shown in FIG.4 according to an embodiment.

FIG. 12 is a cross-sectional view taken along the line I-I′ shown inFIG. 3 according to an embodiment.

FIG. 13 is a cross-sectional view taken along the line I-I′ shown inFIG. 3 according to an embodiment.

FIG. 14 is a flowchart illustrating a method for manufacturing a displaydevice according to an embodiment.

FIG. 15 is a cross-sectional view illustrating a main region and abending region according to an embodiment.

DETAILED DESCRIPTION OF EMBODIMENTS

Example embodiments are described with reference to the accompanyingdrawings. Practical embodiments may be embodied in different forms andshould not be construed as limited to the example embodiments.

Although the terms “first,” “second,” etc. may be used to describevarious elements, these elements should not be limited by these terms.These terms may be used to distinguish one element from another element.A first element may be termed a second element without departing fromteachings of one or more embodiments. The description of an element as a“first” element may not require or imply the presence of a secondelement or other elements. The terms “first,” “second,” etc. may be usedto differentiate different categories or sets of elements. Forconciseness, the terms “first,” “second,” etc. may represent “first-type(or first-set),” “second-type (or second-set),” etc., respectively.

When a first element is referred to as being “on” a second element, thefirst element can be directly on the second element, or one or moreintervening elements may be present between the first element and thesecond element. When a first element is referred to as being “directlyon” a second element, there are no intended intervening elements (exceptenvironmental elements such as air) present between the first elementand the second element.

Spatially relative terms, such as “beneath,” “below,” “lower,” “above,”“upper” and the like, may be used to describe one element or feature'srelationship to another element(s) or feature(s) as illustrated in thefigures. The spatially relative terms may encompass differentorientations of the device in use or operation in addition to theorientation depicted in the figures. For example, if the device in thefigures is turned over, elements described as “below” or “beneath” otherelements or features would then be oriented “above” the other elementsor features. The device may be otherwise oriented (rotated 90 degrees orat other orientations), and the spatially relative descriptors should beinterpreted accordingly.

Same reference numbers may indicate same or similar components.

In the description, a “layer” may mean a portion of the layer. A list ofitems may mean at least one of the listed items. The term “prevention”may mean “mitigation.” The term “FIG.” may be equivalent to “FIG.” shownin the drawings. The term “semiconductor pattern” may mean“semiconductor member.” The term “any one” may mean “at least one.” Theterm “outline” may mean “perimeter section.”

FIG. 1 is a plan/layout view illustrating a display device according toan embodiment. FIG. 2 is a schematic partial cross-sectional viewillustrating the display device according to an embodiment. FIG. 3 is aplan/layout view illustrating signal lines in a bending region of apanel according to an embodiment.

Referring to FIGS. 1 to 3, a display device DD may display a still imageor a moving image. The display device DD may be used in portableelectronic devices such as a mobile phone, a smartphone, a tabletpersonal computer (PC), a smart watch, a watch phone, a mobilecommunication terminal, an electronic notebook, an electronic book, aportable multimedia player (PMP), a navigation device, or anultra-mobile PC (UMPC) and may be used as a display screen of atelevision, a notebook, a monitor, a billboard, or a device for Internetof things (IOT). The display device DD may be one of an organiclight-emitting diode display, a liquid crystal display device, a plasmadisplay device, a field emission display device, an electrophoreticdisplay device, an electro-wetting display device, a quantum dotlight-emitting display device, and a micro light-emitting diode (LED)display device. As an example, the display device may be an organiclight-emitting diode display.

The display device DD may include a display panel DM. The display panelDM may include a flexible substrate including a flexible polymermaterial such as polyimide. Accordingly, the display panel DM may beflexible, bendable, or rollable.

The display panel DM may include a main region MR and a bending regionBD connected to one side of the main region MR. The display panel DM mayfurther include a sub-region SR which is connected to the bending regionBD. Here, “connected” may mean that the two components are made of onematerial and have an integrated shape. The sub-region SR overlaps themain region MR after the bending region BD has been bent.

The display region DA of the display panel DM is disposed inside themain region MR and may display images according to input signals. Thenon-display region NDA of the display panel DM may abut the displayregion DA and may not display images according to input signals. In anembodiment, in the main region MR, a peripheral edge portion of thedisplay region DA, the entire bending region BD, and the entiresub-region SR may constitute the non-display region NDA. The bendingregion BD and/or the sub-region SR may also constitute the displayregion DA.

The main region MR may have a shape that is substantially similar to aplanar shape of the display device DD. The main region MR may be/includea flat region. In the main region MR, at least one edge other than anedge (side) connected to the bending region BD may form a curved surfaceor may be bent in a vertical direction.

The display region DA of the display panel DM may be disposed at acentral portion of the main region MR. The display region DA may includea plurality of pixels. Each pixel may include a light-emitting layer anda circuit layer configured to control an amount of light emitted fromthe light-emitting layer. The circuit layer may include a display line,a display electrode, and at least one transistor. The light-emittinglayer may include an organic light-emitting material. The light-emittinglayer may be sealed by an encapsulation layer.

The display region DA may have a substantially rectangular shape with orwithout rounded corners. The display region DA may have one or more ofvarious shapes such as a square shape, other polygonal shapes, acircular shape, and an elliptical shape.

At least a portion of the non-display region NDA may be disposed at acurved or bent edge of the main region MR. At least a portion of thedisplay region DA and/or at least a portion of the non-display regionNDA may be disposed at a curved or bent edge of the main region MR.

In the main region MR, the non-display region NDA may be disposed aroundthe display region DA. The non-display region NDA of the main region MRmay be span from an outer boundary of the display region DA to an edgeof the display panel DM. A signal line SL and/or a driving circuit forapplying a signal to the display region DA may be disposed in thenon-display region NDA of the main region MR. An outermost black matrixmay be disposed in the non-display region NDA of the main region MR.

The bending region BD may be disposed between the main region MR and thesub-region SR, and at least one outline of two outlines OT-L may includea curved portion (i.e., a curved outline section). For example, the twooutline lines OT-L of the bending region BD may extend from one side ofthe main region MR to one side of the sub-region SR and may be curvedportions having the same curvature. Distances between the two outlinelines OT-L may gradually decrease from the main region MR to thesub-region SR.

In the bending region BD, the display panel DM may be curved, such thatthe sub-region is disposed behind the main region MR without blocking adisplay surface of the display area DA. The bending region BD may have acertain radius of curvature. The bending region BD may have differentradii of curvature for different sections. As the display panel DM isbent in the bending region BD, a surface of the display panel DM facingupward may be changed to face outward and then face downward.

The sub-region SR extends from the bending region BD. The sub-region SRmay extend parallel to the main region MR after bending of the bendingregion BD is completed. The sub-region SR may overlap the main region MRin the thickness direction of the display panel DM. The sub-region SRmay overlap the non-display region NDA and the display region DA of themain region MR.

A width of the sub-region SR may be equal to a (minimum) width of thebending region BD.

A driving chip IC may be disposed in the sub-region SR of the displaypanel DM. The driving chip IC may include an integrated circuitconfigured to drive the display panel DM. In an embodiment, theintegrated circuit may be a data drive integrated circuit whichgenerates and supplies a data signal. The driving chip IC may be mountedon the display panel DM in a sub-region SR. The driving chip IC ismounted on one surface of the display panel DM that is the same surfaceas the display surface. The driving chip IC is mounted on a surface ofthe display panel DM that faces away from the display surface after thebending region BD has been bent so that the driving chip IC may faceaway from the display surface. The driving chip IC may be attached ontothe display panel DM through an anisotropic conductive film or may beattached onto the display panel DM through ultrasonic bonding. A lateralwidth of the driving chip IC may be less than a lateral width of thedisplay panel DM. The driving chip IC may be disposed at a centralportion of the sub-region SR in a lateral direction, and edges of thedriving chip IC may be respectively spaced from edges of the sub-regionSR.

A pad portion PAD (or pads PAD) may be provided at an end of thesub-region SR of the display panel DM, and a printed circuit board FPCmay be connected to the pad portion PAD. The printed circuit board (FPC)may be a flexible printed circuit board or a film.

A plurality of signal lines SL may be disposed in the sub-region SR, thebending region BD, and the main region MR. The signal lines SL may passthrough the bending region BD from the sub-region SR and may extend tothe main region MR. Some of the signal lines SL (for example, aninitialization voltage line, a power line, and a control signal line)may not pass through the driving circuit IC and may extend from pads PADto the main region MR. Some of the signal lines SL (for example, a dataline DL) may pass through the driving circuit IC from pads PAD and thebending region and may extend to the main region MR. The signal lines SLpassing through the driving circuit IC may have a fan-out structure inwhich the signal lines SL are relatively narrowly spaced in thesub-region SR and/or the bending region BD and are relatively widelyspaced in the main region MR in order to cover the entirety of the mainregion MR wider than the driving chip IC. The signal lines SL notpassing through the driving chip IC may pass along an outside of thesignal lines SL passing through the driving chips IC.

The signal lines SL passing through the bending region BD may be bent asthe panel is bent and thus may receive bending stress. The bendingstress may cause a crack or a cutoff/discontinuation of the signal lineSL. In order to minimize/prevent the crack or the cutoff, the signallines SL passing through the bending region BD may be made of asubstantially flexible material.

A first structure CP may be provided on the bending region BD. The firststructure CP may prevent a crack (e.g., in a substrate) from beingpropagated to the signal lines SL. A section of the first structures CPmay be substantially parallel to a curved portion of the bending regionBD.

FIG. 4 is a layout illustrating the signal lines SL in the displaydevice DD according to an embodiment.

Referring to FIG. 4, the display device DD may include a main region MR,a bending region BD, and a sub-region SR. The main region MA may includea display region DA and a non-display region NDA in a plan view. Themain region MR includes a plurality of pixels PX. A region in which thepixels PX are disposed is defined as the display region DA. Thenon-display region NDA may abut the display region DA.

The main region MR includes gate lines GL, data lines DL, emission linesEL, a control signal line SL-D, an initialization voltage line SL-Vint,and a voltage line SL-VDD. Each of the gate lines GL is connected tocorresponding pixels PX of the plurality of pixels PX, and each of thedata lines DL is connected to corresponding pixels PX of the pluralityof pixels PX. Each of the emission lines EL may be parallel to acorresponding line of the gate lines GL. The control signal line SL-Dmay supply control signals to a gate driving circuit GD. Theinitialization voltage line SL-Vint may supply an initialization voltageto the plurality of pixels PX. The voltage line SL-VDD may be connectedto the plurality of pixels PX and may supply a first voltage to theplurality of pixels PX. The voltage line SL-VDD may include a pluralityof lines extending in a first direction DR1 and a plurality of linesextending in a second direction DR2.

The gate driving circuit GD, to which the gate lines GL and the emissionlines EL are connected, may be disposed at one side of the non-displayregion NDA. Among the gate lines GL, the data lines DL, the emissionlines EL, the control signal line SL-D, the initialization voltage lineSL-Vint, and the voltage line SL-VDD, some may be disposed on the samplelayer, and some may be disposed on different layers.

The bending region BD may include two outline lines OT-L, a plurality oflines SL, and a first structure CP. The two outline lines OT-L may beoutlines which extend substantially in the first direction DR1 andconnect the main region MR and the sub-region SR. The lines SL mayconnect lines of the main region MR and lines of the sub-region SR. Aportion of the first structure CP may be disposed between each of thetwo outline lines OT-L and the plurality of lines SL.

FIG. 4 shows a configuration when the bending region BD and edges of themain region MR are not bent. In this configuration, the main region MR,the bending region BD, and the sub-region SR may be sequentiallydisposed in the first direction DR1. A width WT1 of the main region MRin the second direction DR2 may be greater than a width WT2 of thebending region BD in the second direction DR2.

Before cutting, an original substrate SUB_pre shown by a dotted line inFIG. 4 may have a rectangular shape. In order to form the display deviceDD of which four corners are rounded and a connection portion betweenthe main region MR and the bending region BD has an “L” shape, theoriginal substrate SUB_pre may be cut along a cutting line CL using alaser LS (illustrated in FIG. 15). The cutting line CL may be cutthrough a laser cutting method or the like. The first structure CP mayprevent the signal line SL from being damaged by a crack generated whenthe cutting line CL is cut by laser cutting or the like.

FIG. 5 is an equivalent circuit diagram illustrating a pixel PXaccording to an embodiment.

FIG. 5 shows the pixel PX connected to at least one gate line GL, atleast one data line DL, and a voltage line SL-VDD.

The pixel PX includes an organic light-emitting diode OLED as a displayelement. The organic light-emitting diode OLED may be a top emissiontype diode or a bottom emission type diode. The pixel PX may include afirst transistor TFT1 (or a switching transistor), a second transistorTFT2 (or a driving transistor), and a capacitor CAP as a circuit unitconfigured to drive the organic light-emitting diode OLED.

The first transistor TFT1 outputs a data signal applied to the data lineDL in response to a scan signal applied to the gate line GL. Thecapacitor CAP is charged with a voltage corresponding to the data signalreceived from the first transistor TFT1.

The second transistor TFT2 is connected to the organic light-emittingdiode OLED. The second transistor TFT2 controls a driving currentflowing in the organic light-emitting diode OLED in response to aquantity of electric charges stored in the capacitor CAP. The organiclight-emitting diode OLED emits light during a turn-on period of thesecond transistor TFT2.

FIGS. 6 and 7 are partial cross-sectional views illustrating a displaymodule DM according to an embodiment.

FIG. 6 shows a cross section of a portion corresponding to the firsttransistor TFT1 and the capacitor CAP of the equivalent circuit shown inFIG. 5. FIG. 7 shows a cross section of a portion corresponding to thesecond transistor TFT2 and the organic light-emitting diode OLED of theequivalent circuit shown in FIG. 5.

As shown in FIGS. 6 and 7, a barrier layer 10 is disposed on a substrateSUB. The barrier layer 10 may include first, second, and third layers11, 12, and 13. The first to third layers 11 to 13 may be made of aninorganic material. An inorganic layer may include at least one ofsilicon nitride, silicon oxynitride, silicon oxide, titanium oxide, andaluminum oxide. The barrier layer 10 may be optional, may also includean organic layer, or may also include two or more layers. The organiclayer may include a polymer, for example, an acrylic-based organiclayer.

A circuit layer DP-CL is disposed on the barrier layer 10. Asemiconductor pattern AL1 (hereinafter referred to as a firstsemiconductor pattern) of the first transistor TFT1 and a semiconductorpattern AL2 (hereinafter referred to as a second semiconductor pattern)of the second transistor TFT2 are disposed on the barrier layer 10. Thefirst semiconductor pattern AL1 and the second semiconductor pattern AL2may include at least one of amorphous silicon, polysilicon, and a metaloxide semiconductor.

A first insulating layer 20 is disposed on the substrate SUB to coverthe first semiconductor pattern AL1 and the second semiconductor patternAL2. The first insulating layer 20 includes an organic layer and/or aninorganic layer. In particular, the first insulating layer 20 mayinclude an inorganic thin film. The inorganic thin film may include atleast one of silicon nitride, silicon oxynitride, silicon oxide,titanium oxide, and aluminum oxide.

A control electrode GE1 (hereinafter referred to as a first controlelectrode) of the first transistor TFT1, a control electrode GE2(hereinafter referred to as a second control electrode) of the secondtransistor TFT2, and a control electrode E1 may be disposed on the firstinsulating layer 20. The first control electrode GE1, the second controlelectrode GE2, and the first electrode E1 may be formed through the samephotolithography process as the gate lines GL (see FIG. 4). In otherwords, the first electrode E1 may be made of the same material, have thesame stacking structure, and be disposed on the same layer as the gatelines GL.

A second insulating layer 30 is disposed on the first insulating layer20 to cover the first control electrode GE1, the second controlelectrode GE2, and the first electrode E1. The second insulating layer30 includes an organic layer and/or an inorganic layer. In particular,the second insulating layer 30 may include an inorganic thin film. Theinorganic film may include at least one of silicon nitride, siliconoxynitride, silicon oxide, titanium oxide, and aluminum oxide. A secondelectrode E2 may be disposed on the second insulating layer 30. A thirdinsulating layer 40 is disposed on the second insulating layer 30 tocover the second electrode E2. The third insulating layer 40 includes anorganic layer and/or an inorganic layer. In particular, the thirdinsulating layer 40 may include an inorganic thin film. The inorganicfilm may include at least one of silicon nitride, silicon oxynitride,silicon oxide, titanium oxide, and aluminum oxide.

The data lines DL (see FIG. 4) may be disposed on the third insulatinglayer 40. An input electrode SE1 (hereinafter, referred to as a firstinput electrode) and an output electrode DE1 (hereinafter, referred toas a first output electrode) of the first transistor TFT1 may bedisposed on the third insulating layer 40. An input electrode SE2(hereinafter, referred to as a second input electrode) and an outputelectrode DE2 (hereinafter, referred to as a second output electrode) ofthe second transistor TFT2 may be disposed on the third insulating layer40. A first input electrode SE1 is branched from a corresponding line ofthe data lines DL. As an example, the second electrode E2 illustrated inFIG. 6 is disposed between the second insulating layer 30 and the thirdinsulating layer 40. The electrode E2 of the capacitor CAP may bedisposed on the third insulating layer 40. The second electrode E2 maybe formed through the same photolithography process, be made of the samematerial, and have the same stacking structure as the data lines DL andthe power line PL.

The first input electrode SE1 and a first output electrode DE1 areelectrically connected to the first semiconductor pattern AL1 through afirst through-hole CH1 and a second through-hole CH2 passing through thefirst, second, third insulating layers 20, 30, and 40. The first outputelectrode DE1 may be electrically connected to the first electrode E1.For example, the first output electrode DE1 may be connected to thefirst electrode E1 through a through-hole (not shown) passing throughthe second insulating layer 30 and the third insulating layer 40. Asecond input electrode SE2 and a second output electrode DE2 areelectrically connected to the second semiconductor pattern AL2 through athird through-hole CH3 and a fourth through-hole CH4 passing through thefirst, second, third insulating layers 20, 30, and 40. In embodiments,the first transistor TFT1 and the second transistor TFT2 may have abottom gate structure.

A fourth insulating layer 50 is formed on the third insulating layer 40to cover the first input electrode SE1, the first output electrode DE1,the second input electrode SE2, and the second output electrode DE2. Thefourth insulating layer 50 includes an organic layer and/or an inorganiclayer. In particular, the fourth insulating layer 50 may include anorganic material to provide a flat surface. The organic material mayinclude a polymer, and for example, the fourth insulating layer 50 mayinclude an acrylic based organic layer.

At least one of the first, second, third, and fourth insulating layers20, 30, 40, and 50 may be optional according to a circuit structure ofthe pixel. Each of the first, second, and third insulating layers 20,30, and 40 may be defined as an interlayer insulating layer. Theinterlayer insulating layer is interposed between a conductive patterndisposed below the interlayer insulating layer and a conductive patterndisposed on the interlayer insulating layer to insulate the conductivepatterns from each other.

A light-emitting element layer DP-OLED is disposed on the fourthinsulating layer 50. A pixel definition layer PDL, a spacer SPC, and anorganic light-emitting diode OLED are disposed on the fourth insulatinglayer 50.

An anode AE is disposed on the fourth insulating layer 50. The anode AEis connected to the second output electrode DE2 through a fifththrough-hole CH5 passing through the fourth insulating layer 50. Anopening OP is defined in the pixel definition layer PDL and the spacerSPC. The opening OP exposes at least a portion of the anode AE. Thepixel definition layer PDL and the spacer SPC include an organic layerand/or an inorganic layer. In particular, the pixel definition layer PDLand the spacer SPC may include an organic material to provide a flatsurface. The organic material may include a polymer, and for example,the pixel definition layer PDL and the spacer SPC may include an acrylicbased organic layer.

The spacer SPC may be disposed on the pixel definition layer PDL tosupport a mask used when the organic light-emitting diode OLED or thelike is formed. The spacer SPC may substantially cover a face of thepixel definition layer PDL. The spacer SPC may be formed only on apartial region of the pixel definition layer PDL or may be optional.

The light-emitting element layer DP-OLED includes an emission region PXAand a non-emission NPXA adjacent to the emission region PXA. Thenon-emission region NPXA may surround the emission region PXA. Theemission region PXA may be defined to correspond to a partial region ofthe anode AE which is exposed by the opening OP.

A hole control layer HCL may be commonly disposed in the emission regionPXA and the non-emission region NPXA. Although not separately shown, acommon layer such as the hole control layer HCL may be commonly formedin the plurality of pixels PX (see FIG. 4).

An organic light-emitting layer EML is disposed on the hole controllayer HCL. The organic light-emitting layer EML may be disposed only ina region corresponding to the opening OP. That is, the organiclight-emitting layer (EML) may be formed separately for each of theplurality of pixels PX.

An electron control layer ECL is disposed on the organic light-emittinglayer EML. A cathode CE is disposed on the electron control layer ECL.The cathode CE is commonly disposed in the plurality of pixels PX.

The example of the patterned organic light-emitting layer EML isillustrated in the present embodiment, but the organic light-emittinglayer EML may be commonly disposed in the plurality of pixels PX. Inthis case, the organic light-emitting layer EML may generate whitelight. Furthermore, the organic light-emitting layer EML may have amulti-layered structure.

In the present embodiment, a thin film encapsulation layer TFE directlycovers the cathode CE. In the present embodiment, a capping layer may befurther disposed to cover the cathode CE. Here, the thin filmencapsulation layer TFE directly covers the capping layer. The thin filmencapsulation layer TFE may include a plurality of inorganic thin filmsIOL1 and IOL2 and an organic thin film OL.

FIG. 8 is a cross-sectional view taken along a line I-I′ shown in FIG.3. Referring to FIGS. 6, 7, and 8, the bending region BD may include thefirst structure CP and a signal line region SLR. The first structure CPmay include a plurality of dams CD, at least one groove CG formedbetween the dams CD, and a region/gap CR.

The first layer 11, the second layer 12, the third layer 13, the firstinsulating layer 20, the second insulating layer 30, and the thirdinsulating layer 40, which include an inorganic material, may not bedisposed in the region CR and the signal line region SLR. Therefore, itis possible to reduce stress applied to the bending region BD.

The plurality of dams CD may at least one of the first layer 11, thesecond layer 12, the third layer 13, the first insulating layer 20, thesecond insulating layer 30, and the third insulating layer 40 and may bedisposed in a partial region of the first structure CP. The first layer11, the second layer 12, the third layer 13, the first insulating layer20, the second insulating layer 30, and the third insulating layer 40may be inorganic layers. At least one of the fourth insulating layer 50and the pixel definition layer PDL may be further provided on at leastone of the first layer 11, the second layer 12, the third layer 13, thefirst insulating layer 20, the second insulating layer 30, and the thirdinsulating layer 40. The fourth insulating layer 50 and the pixeldefinition layer PDL may be organic layers. At least one groove CG maybe formed between the dams CD. The substrate SUB may be exposed at thegroove CG.

A first structure CP may be disposed between an outline lines OT-L andthe lines SL. The plurality of dams CD may be formed through the samephotolithography process as the barrier layer 10 and the circuit layerDP-CL. The plurality of dams CD may be made of the same materials andhave the same stacking structure as the barrier layer 10 and the circuitlayer DP-CL. The plurality of dams CD may be formed concurrently in aprocess of forming the third through-hole CH3 and the fourththrough-hole CH4 (illustrated in FIG. 7).

The fourth insulating layer 50 (a planarizing film) may be disposed onthe inorganic layer(s) of the plurality of dams CD. Upper surfaces ofthe inorganic layer(s) may be completely covered by the fourthinsulating layer 50. The plurality of dams CD including an organic layermay be formed concurrently in a process of forming the fifththrough-hole CH5 (illustrated in FIG. 7). The fourth insulating layer 50may be disposed at the signal line region SR of the bending region BD,and the signal lines SL may be disposed on the fourth insulating layer50. The signal lines SL disposed on the fourth insulating layer 50 maybe coplanar with the signal lines SL disposed on the main region MR andthe sub-region SR. The signal lines SL may not be disposed on the firstlayer 11, the second layer 12, the third layer 13, the first insulatinglayer 20, the second insulating layer 30, and the third insulating layer40.

An organic layer for forming the pixel definition layer PDL may bedisposed on the fourth insulating layer 50. Upper surfaces of the fourthinsulating layer 50 may be completely covered by the organic layer. Theplurality of dams CD including the organic layer may be formedconcurrently in a process of forming the opening OP of thelight-emitting region PXA (illustrated in FIG. 7). The organic layerforming the pixel definition layer PDL may be disposed on the signallines SL disposed on the fourth insulating layer 50. As a result, thesignal line SL may be prevented from being exposed.

When the outline OT-L is formed through a laser cutting process, a crackmay be generated in the main region MR, the bending region BD, and/orthe sub-region SR. Since the bending region BD is bent, the generatedcrack may continuously grow and may propagate. The dams CD and at leastone groove CG disposed between the dams may be substantially parallel tothe outline OT-L, for preventing the generated crack from propagating tothe signal lines SL. Advantageously, it is possible to reduce defectscaused by stress applied to the bending region BD and improvereliability and manufacturing yield of display devices.

FIG. 9 is an enlarged plan view illustrating the region A shown in FIG.4.

Referring to FIG. 9, the first structure CP may be disposed between theline SL and an outline OT-L in a plan view of the bending region BD whenthe bending region is in a flat configuration. The first structure CPmay be spaced apart from the outline OT-L. The crack mitigationstructure may prevent a crack, which may be generated in a process offorming the outline OT-L, from propagating to the signal lines SL. Atleast one of the two outlines OT-L may include a curved portion. Forexample, a distance between the two outlines OT-L of the bending regionBD may be gradually decreased from the main region MR to the sub-regionSR. The first structure CP may include a dam CD and a groove CG, whichextend along (and substantially parallel to) the curved outline OTL. Thegroove CG may be disposed between dams CD in the second direction DR2different from the first direction DR1. Since the first structure CPincludes the slit-shaped dam CD and the groove CG, even if a crack isgenerated in a portion of the first structure CP, the crack may beprevented from propagating.

As an example, the first structure CP illustrated in FIG. 9 includesthree dams CD and two grooves CG. The first structure CP may furtherinclude a region/spacing/gap CR between the dam CD and the signal lineSL. In the region CR, the organic layer such as the first layer 11, thesecond layer 12, the third layer 13, the first insulating layer 20, thesecond insulating layer 30, and the third insulating layer 40 may beremoved to expose the substrate SUB.

FIG. 10 is an enlarged plan view illustrating the region A shown in FIG.4 according to an embodiment.

Referring to FIG. 10, a first structure CP_1 may be disposed between aline SL and an outline OT-L in a plan view of the bending region BD.

The first structure CP_1 may include a plurality of dams CD_1, and theplurality of dams CD_1 may be disposed along curved sections of anoutline OTL. The dams CD_1 may have island shapes. A plurality ofgrooves CG_1 may be disposed along a first direction DR1 and a seconddirection DR2. The plurality of dams CD_1 may be spaced along theoutline OT-L. The first structure CP_1 may include a gap CR_1 betweenthe dams CD_1 and the signal lines SL.

In comparison with FIG. 9, the dams CD_1 of FIG. 10 may further reducestress generated when the bending region BD is bent.

FIG. 11 is an enlarged plan view illustrating the region A shown in FIG.4 according to an embodiment.

Referring to FIG. 11, a first structure CP_2 may be disposed between aline SL and an outline OT-L in a plan view of the bending region BD. Thefirst structures CP_2 may be disposed along curved sections of theoutline OTL. The first structure CP_2 may include first dams CD_21distributed substantially in the first direction DR1 and second damsCD_22 spaced apart from the first dams CD_21 in the second direction DR2and distributed substantially in the first direction DR1. The firststructure CP_2 may include a gap CR_2 between the second dams CD_22 andthe signal lines SL. The first structure CP_2 may include gaps CG_2between the dams CD_21 and CD_22.

The first dam CD_21 and the second dam CD_22 may have trapezoidal shapesin a plan view.

The first dam CD_21 and the second dam CD_22 may be alternately disposedin the second direction DR2. That is, the first dam CD_21 and the seconddam CD_22 may be disposed in a zigzag pattern in the first directionDR1. A second dam CD_22 may overlap (two neighboring ends of) twoimmediately neighboring first dams CD_21. Therefore, it is possible tofurther reduce stress generated when the bending region BD is bent. Inaddition, a crack passing between adjacent two first dams CD_21 in thefirst direction DR1 may be prevented from propagating to the lines SL bythe second dams CD_22 adjacent in the second direction DR2.

FIG. 12 is a cross-sectional view taken along the line I-I′ shown inFIG. 3 according to an embodiment. Referring to FIGS. 6, 7, and 12, aplurality of dams CD_3 include a first layer 11, a second layer 12, athird layer 13, a first insulating layer 20, and a second insulatinglayer 30, and a third insulating layer 40, which include an inorganicmaterial.

The bending region BD may include a first structure CP_3 and a signalline region SLR. The first structure CP_3 may include dams CD_3, groovesCG_3 formed between the dams CD_3, and a region/gap CR_3.

The first layer 11, the second layer 12, the third layer 13, the firstinsulating layer 20, the second insulating layer 30, and the thirdinsulating layer 40, which include one or more inorganic materials, maynot be disposed in the region CR_3 and the signal line region SLR.Therefore, it is possible to reduce stress applied to the bending regionBD bent toward a rear surface of the main region MR.

The plurality of dams CD_3 may be disposed in a partial region of thefirst structure CP_3. The first layer 11, the second layer 12, the thirdlayer 13, the first insulating layer 20, the second insulating layer 30,and the third insulating layer 40 may be inorganic layers. A substrateSUB may be exposed at the grooves CG_3. A first structure CP_3 may bedisposed between each outline OT-L and the signal lines SL. Theplurality of dams CD_3 may be formed through the same photolithographyprocess as the barrier layer 10 and the circuit layer DP-CL. Theplurality of dams CD_3 may be made of the same materials and have thesame stacking structure as the barrier layer 10 and the circuit layerDP-CL. The plurality of dams CD_3 may be formed concurrently in aprocess of forming the third through-hole CH3 and the fourththrough-hole CH4 (illustrated in FIG. 7).

FIG. 13 is a cross-sectional view taken along the line I-I′ shown inFIG. 3 according to an embodiment.

Referring to FIGS. 6, 7, and 13, a plurality of damps CD_4 include afourth insulating layer 50 and a pixel definition layer PDL, whichinclude an organic material.

The bending region BD may include a first structure CP_4 and a signalline region SLR. The first structure CP_4 may include dams CD_4, groovesCG_4 formed between the plurality of dams CD_4, and a region/gap CR_4.

No inorganic material may be disposed in the region CR_4 and the signalline region SLR. No inorganic layer may be included in the bendingregion BD. Therefore, it is possible to reduce stress applied to thebending region BD.

The plurality of dams CD_4 may be disposed in a partial region of thefirst structure CP_4. The fourth insulating layer 50 and the pixeldefinition layer PDL may be organic layers. A substrate SUB may beexposed at the grooves CG_4.

A plurality of first structure CP_4 may be disposed between each of twooutline lines OT-L and the signal lines SL. All of the first layer 11,the second layer 12, the third layer 13, the first insulating layer 20,the second insulating layer 30, and the third insulating layer 40 may beremoved from the bending region BD in a process of forming the thirdthrough-hole CH3 and the fourth through-hole CH4 (illustrated in FIG.7).

The fourth insulating layer 50 may be disposed on the substrate SUB. Theplurality of dams CD_4 may be formed concurrently in a process offorming the fifth through-hole CH5 (illustrated in FIG. 7). The fourthinsulating layer 50 may be disposed at the signal line region SLR of thebending region BD, and the signal lines SL may be disposed on the fourthinsulating layer 50. As a result, the signal lines SL disposed on thefourth insulating layer 50 may be coplanar with the lines SL disposed onthe main region MR and the sub-region SR.

An organic layer for forming the pixel definition layer PDL may bedisposed on the fourth insulating layer 50 at the plurality of dampsCD_4 and at the signal line region SLR. Upper surfaces of the fourthinsulating layer 50 may be completely covered by the organic layer. Theplurality of dams CD_4 including the organic layer may be formedconcurrently in a process of forming the opening OP of thelight-emitting region PXA (illustrated in FIG. 7). The organic layerforming the pixel definition layer PDL may be disposed on the signallines SL disposed on the fourth insulating layer 50. As a result, thesignal lines SL may be prevented from being exposed.

FIG. 14 is a flowchart of a method for manufacturing a display deviceaccording to an embodiment. FIG. 15 is a cross-sectional viewillustrating a main region and a bending region according to anembodiment.

Referring to FIGS. 4, 14 and 15, the method may include forming at leastone barrier layer 10 on an original substrate SUB_pre (S100).

Before cutting, the original substrate SUB_pre (shown by a dotted linein FIG. 4) may have a rectangular shape. The barrier layer 10 may bedisposed on an entire face of the original substrate SUB_pre. Thebarrier layer 10 may include first, second, and third layers 11, 12, and13. The layers 11, 12, and 13 may be made of one or more inorganicmaterials. An inorganic layer may include at least one of siliconnitride, silicon oxynitride, silicon oxide, titanium oxide, and aluminumoxide.

The method may include forming at least one inorganic layer on thebarrier layer (S110).

A semiconductor pattern AL2 is disposed on the barrier layer 10 of thedisplay region DA. The semiconductor pattern AL2 may include at leastone of amorphous silicon, polysilicon, and a metal oxide semiconductor.A first insulating layer 20 may be disposed on the semiconductor patternAL2. A control electrode GE2 of a second transistor TFT2 may be disposedon the first insulating layer 20. The control electrode GE2 may be madeof the same material as gate lines GL. A second insulating layer 30 anda third insulating layer 40 may be sequentially disposed on the controlelectrode GE2. The insulating layers 20, 30, and 40 may include aninorganic layer. The inorganic layer may include at least one of siliconnitride, silicon oxynitride, silicon oxide, titanium oxide, and aluminumoxide. The first insulating layer 20, the second insulating layer 30,and the third insulating layer 40 may be sequentially stacked on thebending region BD.

The method may include forming dams CD by etching at least the barrierlayer 10 and the above-described inorganic layers in the bending regionBD (S120).

According to an embodiment, the dams CD and grooves CG may be formedconcurrently in a process of forming a third through-hole CH3 and afourth through-hole CH4 (illustrated in FIG. 7).

The forming of the dams CD (S120) may further include applying aplanarizing film (for example, the fourth insulating layer 50) andetching the planarizing film at locations between remaining portions ofthe layers 10, 20, 30, 40, and 50 in the bending region BD.

The fourth insulating layer 50 may be disposed on the inorganic layersof the dams CD. Upper surfaces of the inorganic layer may becompletely/substantially covered by the fourth insulating layer 50.

The dams CD (including an organic layer, i.e., the fourth insulatinglayer 50) and the grooves CG may be formed concurrently in a process offorming a fifth through-hole CH5 (illustrated in FIG. 7). The fourthinsulating layer 50 may also be disposed on a signal line region SLR ofthe bending region BD, and signal lines SL may be disposed on the fourthinsulating layer 50.

The forming of the dams CD (S120) may further include applying a pixeldefinition layer PDL on remaining portions of the planarizing film 50and etching the pixel definition layer PDL at locations between theremaining portions of the planarizing film 50 in the bending region BD.

An organic layer for forming the pixel definition layer PDL may bedisposed on the remaining portions of the fourth insulating layer 50(i.e., the planarizing film 50). Upper surfaces of the remainingportions of the fourth insulating layer 50 may becompletely/substantially covered by the organic layer.

The plurality of dams CD (including the organic layer forming the pixeldefinition layer PDL) may be formed concurrently in a process of formingan opening OP of a light-emitting region PXA (illustrated in FIG. 7).The organic layer forming the pixel definition layer PDL cover thesignal lines SL disposed on the fourth insulating layer 50.

The method may include cutting the original substrate SUB_pre at alocation between two dams CD with (a laser beam provided by) a laser LSto form an outline OT-L of the bending region BD (S130).

In order to form a display device DD of which four corners are roundedand a connection portion between the main region MR and the bendingregion BD has a “L” shape, the original substrate SUB_pre may be cutalong a cutting line CL using the laser LS. The cutting line CL may becut through a laser cutting method or the like. A green/CO₂ laser may beused as the laser.

Grooves CG and dams CD may be formed at opposite sides of the cuttingline CL. Therefore, it is possible to also prevent a crack frompropagating toward/through a to-be-removed portion of the originalsubstrate SUB_pre. Advantageously, the first structure CP may preventsignal lines SL from being damaged by a crack that is generated when thecutting line CL is cut by laser cutting or the like.

Many variations and modifications can be made to the described exampleembodiments without substantially departing from the scope defined inthe claims.

What is claimed is:
 1. A display device comprising: a substrate, whichcomprises a main region, a sub-region, and a bending region connectedbetween the main region and the sub-region and comprising an outlinethat includes a curved outline section, wherein a first end of theoutline is directly connected to one of two opposite edges of the mainregion, wherein a second end of the outline is directly connected to oneof two opposite edges of the sub-region, wherein the curved outlinesection is connected between the first end of the outline and the secondend of the outline, and wherein the two opposite edges of the sub-regionare positioned closer to each other than the two opposite edges of themain region; pixels disposed on the main region; and a structuredisposed on the bending region, wherein a section of the structure issubstantially parallel to the curved outline section.
 2. The displaydevice of claim 1, wherein a first end of the structure is positionedcloser to the main region and farther from a center of the bendingregion than a second end of the structure.
 3. The display device ofclaim 1, wherein the structure comprises dams, wherein the dams arespaced from each other and include a dam, and wherein a section of thedam is substantially parallel to the curved outline section of thebending region.
 4. The display device of claim 3, wherein the damcomprises an inorganic layer.
 5. The display device of claim 4, whereinthe inorganic layer comprises at least one of a first insulating layer,a second insulating layer, and a third insulating layer.
 6. The displaydevice of claim 3, further comprising: a first organic layer overlappingthe bending region; and a signal line provided on the first organiclayer.
 7. The display device of claim 6, further comprising a drivingchip disposed on the sub-region and electrically connected through thesignal line to at least one of the pixels.
 8. The display device ofclaim 7, further comprising a second organic layer disposed on the firstorganic layer and covering the signal line.
 9. The display device ofclaim 8, wherein the dam comprises at least one of a first organic partand a second organic part, wherein a material of the first organic partis identical to a material of the first organic layer, and wherein amaterial of the second organic part is identical to a material of thesecond organic layer.
 10. The display device of claim 9, wherein the damfurther comprises an inorganic part, wherein the inorganic part ispositioned between the bending region and the at least one of the firstorganic part and the second organic part.
 11. The display device ofclaim 6, wherein the first organic layer is spaced from the dams. 12.The display device of claim 11, wherein the substrate is partiallyexposed between the dam and the first organic layer.
 13. The displaydevice of claim 3, wherein the substrate is partially exposed betweenthe dams.
 14. The display device of claim 3, wherein the dam extendscontinuously from an edge of the main region to an edge of thesub-region.
 15. The display device of claim 3, wherein the dams arespaced from each other in a first direction and are spaced from oneanother in a second direction different from the first direction. 16.The display device of claim 15, wherein the dam has a trapezoidal shapein a plan view of the bending region and is a first dam, wherein thedams further include a second dam, wherein no intervening dam ispositioned between the first dam the second dam, and wherein the firstdam and the second dam are not all aligned.